If I understand your requirement correctly that you want to create the dax measure for Drops and Customers to get the outcome.
For your scenario, if you want to get the outcome you share, I'm afraid you should create the column Drops and Customers in Excel or create the custom columns in Power Query Editor.
Then you could unpivot the columns Drops and Customers in Power Query Editor and you will get the outcome in Power BI.
Dax may not achieve your requirement.
Community Support Team _ Cherry Gao
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